Upside - they did due diligence, they signed a contract, they made a pre-payment of US$12m. Contract last settlement due date 31/01/2015.
Downside - not subject to Australian law in practical terms - oops....
The concept of "what if GXY decided not to sell after all" vs "we have decided not to buy unjder current terms" doesn't exist. All one-sided as usual.